1. Field:
The present invention relates generally to the disposal of used containers. More particularly, the present invention relates to the crushing of used containers prior to the disposal thereof. Still more particularly, the present invention relates to a method for collapsing and totally compacting metal containers and a device for practicing the method.
2. The disposal of a used container, by whatever means, has always been accompanied by the problem, or at least the considerable inconvenience, that an empty container occupies a considerable volume in relation to its weight. To minimize this problem or inconvenience, an empty container consigned to disposal is often first crushed or compacted in order to reduce its volume, a procedure that requires, at least for metallic containers, a force greater than that which can normally be easily and effectively applied by hand. As recycling of metal containers has come more into fashion, moreover, the significance of this problem has increased since recycle receiving stations often do not have the space to accept metal containers except in a compacted form. Accordingly, a number of hand operated metal container crushing or compacting devices have been proposed, the simplicity and effectiveness of which vary widely.
Existing hand operated metal container or can compacting devices are broadly based on one of two methods of compacting. One such method involves applying a compressive force to one or both ends of a container in order to collapse the container sidewall along the longitudinal axis of the container, thereby forcing the two container ends into flattened contact with each other. A device based on this method of compacting is shown in U.S. Pat. No. 4,188,875. A drawback to this method is that it requires a greater force to overcome the initial lateral resistance of the can sidewall than is subsequently required to compress the sidewall along the longitudinal axis of the container, a situation that could lead to hand or other injury to the operator if this is not taken into account in operation of the device. This drawback is recognized in U.S. Pat. No. 4,248,144 in which a rather complicated arrangement is suggested to eliminate its hazards.
The other method of container compacting involves the application of a compressive force to the sidewall of the container along substantially its entire length in order to collapse the sidewall inwardly upon itself so as to totally flatten the container. A device based on this method of container compacting is disclosed in U.S. Pat. No. 3,901,141. A drawback to this method, however, is that both the resistance of the container ends, as well as that of the container sidewall, must be overcome in order for the sidewall to collapse inwardly upon itself. It has been proposed to lessen the resistance of the container ends by first removing the ends as by cutting, a procedure that necessarily calls for more complicated device than might be desired. It has also been proposed to first buckle one or both ends of the container inwardly towards each other by applying a compressive force to the container ends at an angle to the longitudinal axis of the container. A compressive force is then applied along the length of the container collapsing the container ends together with the container sidewall inwardly. Various devices incorporating this proposal are illustrated in U.S. Pat. No. 3,766,849; 4,212,242; 4,248,144 and 4,292,891, all of which devices are, for the most part, more complicated than one would desire.